X shaped chromosomes are linked together at a place called the centromere
Answer:
The nucleic acid DNA is an organic compound. DNA is made up of repeating subunits called nucleotides . Each DNA molecule consists of 2 long chains of nucleotides. A DNA nucleotide has three parts: a sugar molecule called deoxyribose ; a phosphate group, and a molecule that is referred to as a nitrogenous base because it contains nitrogen atoms. The deoxyribose sugar and the phosphate group are identical in all DNA nucleotides. However, the nitrogenous base may be any one of 4 different kinds. The four nitrogenous bases found in DNA nucleotides are adenine, thymine, cytosine, and guanine. The two strands of a DNA molecule are held together by hydrogen bonds.
Explanation:
These are biology facts.
I'm pretty sure it would be A.
Answer:
Because the leading strand is synthesized continuously while the lagging strand is discontinuously synthesized.
Explanation:
Two DNA strands have opposite polarity, that is, the 5' end of one strand lies opposite to the 3' end of the other strand. However, DNA replication can occur in 5' to 3' direction only since the formation of phosphodiester bonds require the presence of nucleophile 3' OH to attack the 5' phosphate of an incoming deoxyribonucleotide.
The problem is solved by the synthesis of the leading strand continuously and the synthesis of the lagging strand in a discontinuous manner. Lagging strand synthesis requires the formation of primers and their elongation to form Okazaki fragments that may have few hundreds to few thousands of nucleotides. Removal of primers from Okazaki fragments is followed by joining them together to make the long lagging strand. The discontinuous replication of the lagging strand makes the replication at the leading strand ahead of it.